Engine reverse gear



Dec. 4

E. l.. Scl-{ELLENSl ENGINE REVERSE GEAR Patented Dec. 4, 1923.

NETE@ SQTS" 1,476,470/ ortica.

EUGENE LEVERNG- SCHELLENS, OF GROTON, CONNECTCUTJ ENGINE REVERSE GEAR.

Application filed November 5, 1919. Serial No. 335,943.

To all whom t may concern:

Y Be it known that I, EUGENE LEVERING SoHELnENs, a citizen of the UnitedStates of America, and residing at Broad Street, in the town of Groton,in the State of Connecticut, in the United States of America, haveinvented a new and useful Engine Reverse Gear, of which the following isthe specification.

rlhe invention relates to engine reverse gear as described in thepresent specification and illustrated in the accompanying drawings thatform part of the same.

The invention consists essentially of the novel means employed, wherebyan eXpansile fluid chamber changes position in relation to an adjoiningexpansion chamber following the manual operation of the communicatingvalve and incidentally operates the reach rod. f

The objects of the invention are to accurately adjust the position ofthe reach rod at a comparatively slight manual exertion; to eliminatethe troubles of leakages, condensation and varying pressures incident tosteam reverse gears; to facilitate the change over` to a manuallyoperated gear throughout in the event of accident; to avoid creeping ofthe reverse mechanism due to the self actuation of the driving parts;and generally to provide an economical, durable and efficient reversegear.

In the drawings, Figure l is a longitudinal sectional view'of the gear.

'Figure 2 is a cross sectionall view through the reach rod connection.

-Figure 3 is an enlarged longitudinal sectional view of thecommunicating valve and ports. Y

Figure 4 is a cross sectional view through the communicating valves andports.

Figure 5 is a diagrammaticv view, showing the plan of communication toexpansion chamber,

Figure 6 is a diagrammatic View, showing the plan of communication toexhaust.

Like numerals of reference indicate corresponding parts in each figure.`

Referring to thedrawings, the cylinder 1v is shown as formed with thereduced end 2 joined by the neck portion 3 to the expansion chamber 4,in which the piston 5'operates, the latter having a communicatingopening 6 with closures as set forth hereinafter.

The inlet 7 lfor the eXpansile fluid to `the cylinder l` is at the neckportion 3, which,

in the neutral positions of the piston 5 and the smaller piston 8, ismidway between said pistons. The head 9 of the piston 8 projectsinwardly towards the piston 5 from the face 10 and is hollow and hasthepassages 11 and 12 communicating with the passage 13 between thecylinder and the recessed walls of the cylindrical piston follower 15 ofthe said piston 8 and the outlet opening 14.

The passage 11 is connected by the hollow piston rod 16 to the expansionchamber 4 through the piston 5 and the passage in this rod 16communicates with the communicating opening 6 by means of the passage17.v

The reach rod 18 is secured tothe piston 8 in the interior of thefollower 15 by the pivot pin 19, which may be driven out of the hole 2Oby a tool inserted lin the hole 21 in the cylinder 1, said holes beingclosed by the plugs 22 and 23 respectively. y

The parallel lugs 24 and the parallel lugs 25 are arranged in pairsrespectively and both form part with the tongue 26 sliding in thegrooved way 27 rigid with the cylinderV l1. The way 27 is mounted on thereduced tween the pistons through'the yoke and i registering with theslot 33.

The valve seat 35 is inserted in the botto end `of said opening, havingthe port/36 through the centre thereof registering with the passage 17and the port 37 leading from the'opening 6 to the expansion chamber 4.

rlhe head plate 38 closes in the opening 6A on the expansion chamberside and the :head plate 39 closes in the remainder of the'opening 6 onrthe piston rfilled bythe yoke V30, both plates 38 and 39 forming stopsand limiting the movement of the yoke 30.v Y 1 The slide valve 40 isenclosed in the centhe port 41in the under side, said port 4l beingintended .to form the fluid passage in connecting the ports A36 and 37in exhausting the fluid `from the expansion chamber 4.

They operating reach rod 42 is'swivelly connected to the screw43 of thescrew opertom of the opening 6 and extends from end 105 tral recess 31of the yoke and is formed with of hand. lever common v'to the operationofv ating drive, the said screwy turning in the slidingnuts 44 and 45slidably secured to the cylinder 1, the gear wheel 46 being` mounted asthe head of the screw 43 and serving as a hand-whee1-for operating thehand throughout and in making this change,

over, the ,rod 18 isremovedfrom its connection,l with the piston 8 bytakingout the plugs 22 and 23 andfv driving out the pin-19 andthenconnecting theV said rod 18 to the lugs 25. Inlthisuway the differentialpiston mechanismis entirely cut out andthe main reachrodlis` directlyconnected to the operatinggear by they operating reach rod and screw.screw drive isnot by any means essential to this' invention as a levercan be used withthe same results, furthermore ythis inventionmay beoperatedby the old type reach rods on locomotives, therefore inequippingga locomotive in service with this reverse gear `comparativelyfew changes are necessaryas the lever reach-rod may be .attached to ,thelever asy itr standsin the cab.

The gland'49 is securedto the extremity of the reduced end2 of thecylinder and encirclesthe follower 15 adjacent to the out- 1et.,14. y

Thedrain cock 50 isf secured in the wall-of the cylinderr 1 near to theend of the eXpansion v chamber y4.

In describingvthe operation ofy this machine tlie explanation will beconfined to the use of steam for theyclearer understanding of the:loperative relations of they several parts.

The steam. chamber between the differential pistons i-s constantlyconnected with the steamboiler, consequently this chamber will containlive steam,which is maintained at boiler pressure.

The admissionl of. steam to the piston chamberV drives the. piston inthe` direction of thefeXpan-sionchamber 4 untilv the yoke .30 reachesthe head` plate in the piston chamber side of the opening 6, for thepiston 5 is travellingand the yoke is normally stationary. The movementof the piston in rela'- tion to the stationary yoke siides the valveseat and opens the port 37 which communi- Cates with the passage 34, inwhichthe steam is at'boiler pressure, the same as in the piston chamber,therefore the steam is imme- Y diately admitted tov the expansionchamber 4, thus; bringing pressure on the'outside of the piston 5, untilthel piston 5 is balanced. The further movement of the slide valve is tobring the ports 36 and37 both in register with the port 41 of said'valve andA as the port. 36 is in direct connection with the eX- haustpassages,fthe. steam will exhaustfrom the expansion chamber, until abalance is assured.

The operating reach rod is, as explained, actuated by screw drivemechanism or lever mechanism under the control-of theengineer-in-charge, therefore if he moves his lever or screw the yoke 30will move and consequently the vaive40 and providing it is desirable topush the main reach rod, the port 37 is opened to admit liveiste'am intothe. expansion chamber 4.. rlhefpiston now begins to move ina directionaway from the expansion chamber and the reach rod, which isconnectedwith the piston 8 is correspond; ingly movedandpushed ina ydirection.away from the gear andV so longas the lever orscrew pressure isfkepton,.the main" reach rod will be held to that position, butimmediately-it is released, the ,ioatingl position of the piston chamberis automatically resumed and this may be hastened by operating the driveor leverage in the other direction. The continuedoperation inthe otherdirection effects apullonrthe main reach rod, as the steam-isexhaustedifrom the. expansion chamber 4 andthe' larger pistonis ofcourse movedalongin.saidexpansion chamber, until the operator releasesthe screw or lever, or brings it backto neutral.`

It has already been explained .how this gear maybe changed over toa'vhand operated gear throughout, butv ,it vmay here be pointed outas anextremely important feature of the invention, as ta'voids detentionslhaving a reduced end anda constantly open' inlet at the reducedportion, a piston in said f' cylinder, of lesser-surface .areaon the oneside than the other and self.l adjustableby pressures in regardtoits-.balancedposition, a valve mechanism Vmountedin said pistonl andadapted to co-operate with said-piston'V having ports and passagesineffecting the operation thereof to the desiredposition, an: operatingrod holding said valve rig-idly n notwithstanding the. movement,V of:the piston and a reachrod forming 4anopera'ting member. v

2.7 1nk Van engine'u reverse gean. a cylinder having. a reduced portion,,a..piston ,fttiligr the reduced portion, a. piston. fitting.. the:ylarger portion, a hollow rod,.jo ining said pistons andl spacing;Y themy,to form an. eXpansion. chamber, a reach rod secured .tothe smallerpiston1 a valve mechanism mounted in said larger piston and controllinga communicating passage therethrough and having a seat with portsconnected with said hollow rod and the expansion chamber beyond saidfluid chamber, a valve on said seat, a yoke engaging said valve and alstem from said yoke, and a hand operated member connected with saidstem.

3. In an engine reverse gear, a cylinder having a reduced portion, apiston fitting the reduced portion, a piston fitting the larger portion,a hollow rod, joining said pistons and spacing them to form an eXpansionchamber, a reach rod secured to the smaller piston, a valve mechanismmounted in said larger piston and controlling a communicating passagetherethrough and having a seat with ports connected with said hollow rodand the expansion chamber beyond said fluid chamber, a valve on saidseat, a yoke engaging said valve and a stem from said yoke, and a screwdrive operatively connected with said stem.

4. In an engine reverse gear, a cylinder having a reduced portion, apiston fitting the reduced portion, a piston fitting the larger portion,a hollow rod joining said pistons and spacing them to form an expansionchamber, a reach rod secured to the smaller piston, a valve mechanismmounted in said larger piston and controlling a communicating passagetherethrough and having a seat with ports connected with said hollow rodand the expansion chamber beyond said fluid chamber, avalve on saidseat, a yoke engaging said valve, and a stem terminating in a double setof lugs, one set of lugs being adapted as a change over for the mainreach rod, and an operating reach rod from the other set of lugs adaptedfor manual opera-tion.

5. In an engine reverse gear, a front piston and a rear piston, a hollowpiston rod joining said pistons for exhausting through prepared passagesin the wall of the rear piston, a valve and gear and contiguous partsintroduced into the front piston and having a port leading through thelatter and a port to said hollow rod, a cylinder having an inlet betweensaid pistons and an outlet beyond the rear piston and connected withsaid hollow rod, a manually operated member connected with said valvegear, and a reach rod connected to the rear piston.

Signed at the city of Montreal, Province of Quebec, Dominion of Canada,this 1st dayv of November, 1919.

EUGENE LEVERING SCHELLENS.

